The start()
method of the MessagePort
interface starts the sending of messages queued on the port. This method is only needed when using EventTarget.addEventListener
; it is implied when using MessageChannel.onmessage
.
Note: This feature is available in Web Workers.
Syntax
port.start()
Returns
Void.
Parameters
None.
Example
In the following code block, you can see a handleMessage
handler function, run when a message is sent back to this document using onmessage
:
channel.port1.onmessage = handleMessage; function handleMessage(e) { para.innerHTML = e.data; }
Note: For a full working example, see our channel messaging basic demo on Github (run it live too).
Another option would be to do this using EventTarget.addEventListener
, however, when this method is used, you need to explicitly call start()
to begin the flow of messages to this document:
channel.port1.addEventListener('message', handleMessage, false); function handleMessage(e) { para.innerHTML = e.data; textInput.value = ''; } channel.port1.start();
Specifications
Specification | Status | Comment |
---|---|---|
WHATWG HTML Living Standard The definition of 'start()' in that specification. |
Living Standard | No difference from HTML5 Web Messaging. |
HTML5 Web Messaging The definition of 'start()' in that specification. |
Recommendation | W3C version of the spec |
Browser compatibility
See also
Document Tags and Contributors
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Contributors to this page:
stevenwdv,
nmve,
libbymc,
Sebastianz,
chrisdavidmills,
fscholz,
kscarfone
Last updated by:
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